metamorphic

Weathered quartz-rich pebble, possibly quartzite or granite fragment

Quartzite (mostly SiO₂), though the specimen may contain feldspar and other silicates

AI-generated identification · may be incorrect

Light gray to cream, granular, dull-to-glassy luster, no obvious cleavage, and rounded by abrasion; quartzite hardness is about 7 Mohs, while mixed granite fragments are typically 6–7.

Identified September 7, 2026More metamorphic →

Explore Weathered quartz-rich pebble, possibly quartzite or granite fragment in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Light gray to cream, granular, dull-to-glassy luster, no obvious cleavage, and rounded by abrasion; quartzite hardness is about 7 Mohs, while mixed granite fragments are typically 6–7.

Formation & geological history

Likely formed from quartz-rich sandstone metamorphosed into quartzite, then weathered and transported as a stream or beach pebble; its precise geological age cannot be determined from the image.

Uses & applications

Primarily a curiosity or teaching specimen; quartzite is used as crushed stone, aggregate, paving, and building stone, while attractive pieces may be tumbled or polished.

Geological facts

The rounded shape indicates substantial mechanical wear. A strong scratch test against ordinary glass can help distinguish quartz-rich material from softer limestone or altered rock.

Field identification & locations

Common in gravel beds, stream channels, beaches, and glacial deposits worldwide; inspect for sugary quartz texture, lack of fizz in dilute acid, and hardness sufficient to scratch glass.